Health benefit assessment of continuous improvement of air quality action plan in China

To continuously improve air quality and protect public health, China issued the Continuous Improvement of Air Quality Action Plan in 2023. This study introduces a dual-pollutant health impact trade-off analysis to explore the effects of the action plan on air quality (including PM_2.5 and O₃ concentrations), health, and economic consequences in China. First, air quality before and after the implementation of the action plan was explored in three key regions using the air quality model, introducing updated chemical mechanisms to capture the nonlinear concentration changes. Second, the health benefits of avoiding premature deaths attributable to PM_2.5 and O₃ exposure, due to improvements in air quality, were estimated using the Global Exposure Mortality Model. Third, the economic impacts associated with human health improvements were monetised based on the willingness-to-pay method. The main findings are summarised as follows. (1) Regarding air quality impacts, through the implementation of the action plan, the annual mean PM_2.5 concentrations across three key regions would decrease by 1.05, 0.3, and 0.18 μg/m³ on average in the Fen-Wei Plain, Beijing-Tianjin-Hebei and surrounding areas, and Yangtze River Delta region, respectively, during 2020-2025; in contrast, the increases in O₃ concentrations would reach 3.08, 1.03, and 0.91 μg/m³ on average, respectively, during this period. (2) Concerning health impacts, the action plan would prevent approximately 5581 (95% confidence interval (CI): 4720-6378) premature deaths from PM_2.5 reductions but lead to 3043 (95% CI: 1136-4547) additional deaths from O₃ increases in three key regions. (3) From an economic perspective, the action plan would generate economic benefits of 1414.14 (95% CI: 1195.05-1617.21) million USD from PM_2.5-related avoided premature deaths, but economic disbenefits of 993.33 (95% CI: 368.67-1492.98) million USD from O₃-related increased premature deaths in the three key regions.